This invention relates to a system for dispensing adhesive imbalance correction weight for correcting imbalance in rotary elements. The invention is disclosed in the context of correcting imbalance in vehicle wheel-and-tire assemblies. The invention is believed to be useful in other applications as well.
In recent years, some vehicle wheel designs have evolved that do not permit the use of pound-on imbalance correcting weights on the outwardly facing, or xe2x80x9ccurbxe2x80x9d side of the wheel. These wheels are sometimes called xe2x80x9cflangelessxe2x80x9d or xe2x80x9csoft facexe2x80x9d wheels. Flangeless or soft face wheels generally require adhesive weights to be applied from the car side of the tire and wheel assembly to the inside diameter of the wheel to correct some portion of the imbalance in the assembly. Currently, an operator selects a specific size weight from a row of bins, removes the protective tape and applies the weight to the wheel. This process is slow and it is easy for the operator to select the wrong weight. In addition, typical currently available adhesive weights are made from pieces of lead with protective coatings to reduce the likelihood of direct worker contact with the lead. These one-piece weights are preformed to a specific wheel radius. Workers sometimes reshape the weights to the radius of a wheel for which the weights were not originally made. Otherwise, optimal adherence of the adhesive weight will not be achieved. These characteristics lead to additional work and rework at imbalance correcting stations for wheel and tire assemblies.
Another currently available system pulls extruded lead, with adhesive already applied, from a coil of extruded lead, forms the extruded lead to a particular radius, and then cuts the amount of extruded lead necessary to achieve a particular amount of imbalance correction. Weights formed using this system leave the ends of the lead weights exposed to contact with workers. This exposed lead is unacceptable to many manufacturers. Also, as noted, this system forms the extruded lead to only one radius. Again, this means that if the weight is to be applied to a wheel having another radius, the worker must reshape the weight to the desired curvature. Additionally, lead is heavy, resulting in the coils having limited capacity. This results in frequent replacement of the somewhat unwieldy coils.
According to several aspects of the invention, apparatus is provided for dispensing imbalance correction weight for attachment to a rotary element to reduce an imbalance in the rotary element. The imbalance correction weight includes one or more individual weights provided on a length of tape.
According to one of these aspects of the invention, the apparatus includes a blade and an anvil which cooperate to cut the tape, and a sequencer for sequencing relative movement of the blade and the anvil in a blade-moving stroke and an anvil-moving stroke, respectively.
Illustratively according to this aspect of the invention, the sequencer includes a spring for biasing the blade away from the anvil to sequence the anvil-moving stroke to occur before the blade-moving stroke.
Further illustratively according to this aspect of the invention, the apparatus includes a blade carriage carrying the blade, and an anvil carriage carrying the anvil. The blade carriage and the anvil carriage are mounted on a frame for relative movement.
Additionally illustratively according to this aspect of the invention, the sequencer includes a stop for engaging the anvil carriage to end the anvil-moving stroke.
Illustratively according to this aspect of the invention, the stop includes a first adjustable member for adjusting the excursion of the anvil during the anvil-moving stroke.
Further illustratively according to this aspect of the invention, the stop includes a second adjustable member engaging the anvil carriage to position the anvil before the anvil-moving stroke. The first adjustable member engages the anvil carriage to end the anvil-moving stroke.
Additionally illustratively according to this aspect of the invention, a motor is coupled to the blade carriage and the anvil carriage for moving the blade during the blade-moving stroke and the anvil during the anvil-moving stroke.
Illustratively according to this aspect of the invention, the motor includes a cylinder and a rod extensible from the cylinder in response to fluid flow. The cylinder is coupled to one of the anvil carriage and the blade carriage. The rod is coupled to the other of the anvil carriage and the blade carriage.
According to yet another aspect of the invention, the apparatus includes a tape divider for dividing the tape, and a sensor for counting individual weights. The tape divider divides the tape when the sensor has counted a number of individual weights necessary to reduce the imbalance.
Illustratively according to this aspect of the invention, the sensor is a photosensor.
Additionally illustratively according to this aspect of the invention, the sensor is positioned immediately upstream from a dividing zone in which the tape divider operates to divide the tape.
Further illustratively according to this aspect of the invention, the apparatus includes a guide for directing the imbalance correction weight toward the tape divider. The guide includes a wall and a bias mechanism for sequentially biasing one or more individual weights against the wall. The sensor is positioned to count a weight when the weight is biased against the wall by the bias mechanism.
Illustratively according to this aspect of the invention, the wall includes an opening. The sensor senses the weight through the opening.
Further illustratively according to this aspect of the invention, the guide includes a channel through which the imbalance correction weights pass on their way to the tape divider, and the sensor is positioned across the channel from the bias mechanism.
According to another aspect of the invention, the apparatus includes a tape divider for dividing the tape and a guide for directing the imbalance correction weight toward the tape divider. The guide includes a wall and a bias mechanism between which the imbalance correction weight is directed. The bias mechanism yieldably biases a portion of the imbalance correction weight against the wall.
Illustratively according to this aspect of the invention, the bias mechanism includes a body and a first bias element for yieldably biasing a portion of the body toward the wall to bias a portion of the imbalance correction weight against the wall.
Further illustratively according to this aspect of the invention, the apparatus including a frame. The body is mounted on the frame for pivotal movement in response to variations in the size of the individual weights and the compressibility of the tape.
Additionally illustratively according to this aspect of the invention, the bias mechanism includes a second bias element for yieldably biasing the portion of the body away from the wall to maintain a space between the body and the wall when no imbalance correction weight is between the body and the wall.
Illustratively according to this aspect of the invention, the first bias element exerts a force on the body of a first distance from a pivot axis of the body and the second bias element exerts a force on the body at a second distance from the pivot axis, the first distance being greater than the second distance.
Further illustratively according to this aspect of the invention, each of the first and second bias elements includes a plunger and a spring yieldably biasing the plunger against the body.
According to yet another aspect of the invention, the individual weights are provided on a first side of a length of tape, and a removable backing is provided on a second side of the tape. The apparatus includes a tape divider for dividing the tape and a driver for removing the backing from the second side to move the imbalance correction weight toward the tape divider.
Illustratively according to this aspect of the invention, the driver includes a wheel and a movable belt for pulling on a portion of the backing removed from the second side.
Further illustratively according to this aspect of the invention, the movable belt is trained about at least two pulleys.
Additionally illustratively according to this aspect of the invention, the portion of the backing removed from the second side passes between the wheel and the movable belt.
Further illustratively according to this aspect of the invention, the apparatus includes a motor coupled to a first one of the pulleys to drive the belt.
Illustratively according to this aspect of the invention, the driver includes a clutch-and-brake mechanism coupled to the motor and the first one of the pulleys.
Additionally illustratively according to this aspect of the invention, the apparatus includes a device for yieldably urging the wheel against the movable belt with the portion of the backing between the belt and the wheel.
Illustratively according to this aspect of the invention, the device includes a pivotal arm rotatably supporting the wheel and a spring coupled to the arm to bias the wheel toward the belt.
According to several other aspects of the invention, methods are provided for dispensing imbalance correction weight for attachment to a rotary element to reduce an imbalance in the rotary element. The imbalance correction weight includes one or more individual weights provided on a length of tape.
According to one of these aspects of the invention, each individual weight has an outer surface covered by a coating. The method includes dividing the tape while maintaining the coating on the individual weights to provide the imbalance correction weight.
Illustratively according to this aspect of the invention, dividing the tape to provide the amount of imbalance correction weight includes moving a blade and an anvil relative to the tape so that the blade and anvil cooperate to divide the tape.
Further illustratively according to this aspect of the invention, the method includes providing a gap between the pair of adjacent individual weights. Moving a blade and an anvil relative to the tape so that the blade and anvil cooperate to divide the tape includes moving the anvil between a pair of adjacent individual weights into contact with a first side of the tape. Moving the anvil between a pair of adjacent individual weights into contact with a first side of the tape includes moving the anvil into the gap.
Additionally illustratively according to this aspect of the invention, moving a blade and an anvil relative to the tape so that the blade and anvil cooperate to divide the tape includes moving the blade into contact with a second side of the tape after moving the anvil between the pair of adjacent individual weights into contact with the first side of the tape.
Illustratively according to this aspect of the invention, providing a gap includes changing a direction of motion of the tape to open up the gap between adjacent individual weights.
Further illustratively according to this aspect of the invention, moving a blade and an anvil relative to the tape so that the blade and anvil cooperate to divide the tape includes yieldably biasing the blade against movement toward the tape.
Additionally illustratively according to this aspect of the invention, moving the anvil into the gap and the blade toward the anvil to divide the tape includes moving the anvil and the blade along paths that form oblique angles with a direction of motion of the imbalance correction weight prior to the change in the direction of motion of the imbalance correction weight.
Illustratively according to this aspect of the invention, moving the anvil into the gap and the blade toward the anvil to divide the tape includes moving the anvil into contact with at least one of the adjacent individual weights to widen the gap.
According to a further aspect of the invention, the method includes counting a desired number of individual weights, and dividing the tape when the desired number of individual weights has been counted to provide the amount of imbalance correction weight.
Illustratively according to this aspect of the invention, the method includes biasing the desired number of individual weights toward a sensor that counts the desired number of individual weights.
Further illustratively according to this aspect of the invention, counting the desired number of individual weights includes counting the desired number of weights using a photosensor.
Additionally illustratively according to this aspect of the invention, counting the desired number of individual weights includes counting the individual weight next adjacent the desired number of individual weights.
According to another aspect of the invention, the method includes moving the imbalance correction weight through a guide including a wall, yieldably biasing a portion of the imbalance correction weight against the wall, and dividing the tape to provide the amount of imbalance correction weight.
Illustratively according to this aspect of the invention, yieldably biasing a portion of the imbalance correction weight against the wall includes sequentially biasing one or more individual weights against the wall adjacent an outlet of the guide.
According to another aspect of the invention, the individual weights are provided on a first side of a length of tape. A removable backing is provided on a second side of the tape. The method includes removing the backing from a portion of the second side, moving the imbalance correction weight toward a tape divider in response to removing the backing from the portion of the second side, and dividing the tape at the tape divider to provide the amount of imbalance correction weight.
Illustratively according to this aspect of the invention, removing the backing from a portion of the second side includes moving a portion of the backing already removed from the second side and the tape from which the backing has been removed in different directions.
Additionally illustratively according to this aspect of the invention, removing the backing from a portion of the second side includes pulling on a portion of the backing previously removed from the second side.
Illustratively according to this aspect of the invention, pulling on a portion of the backing previously removed from the second side includes passing the portion of the backing previously removed from the second side between a movable belt and a wheel.
Further illustratively according to this aspect of the invention, the method includes directing the backing removed from the second side from between the belt and the wheel into a collection container.
According to another aspect of the invention, an apparatus is provided for attaching an imbalance correction weight to a rotary element to reduce an imbalance in the rotary element. The imbalance correction weight includes one or more individual weights provided on a first side of a length of tape. The tape includes a second side for attachment to the rotary element. The apparatus includes a body including a first surface for pressing the second side against the rotary element, and a clamp including a pair of jaws providing a channel. The jaws are movable relative to the body between extended orientations in which the channel is beyond the first surface and retracted orientations in which the channel is not beyond the first surface.
Illustratively according to this aspect of the invention, each jaw includes a convex second surface for contacting the rotary element to move the imbalance correction weight out of the channel.
Further illustratively according to this aspect of the invention, the first surface includes a convex surface.
Additionally illustratively according to this aspect of the invention, the channel includes a groove defined in each jaw.
Illustratively according to this aspect of the invention, each groove is bounded on one side by a flange. The flanges facing each other. The flanges cooperate to hold the weight yieldably when the jaws are in the retracted orientation.
Further illustratively according to this aspect of the invention, the clamp includes a bias mechanism for yieldably biasing the jaws toward each other.
Additionally illustratively according to this aspect of the invention, one of the body and the jaws includes at least one slot. The other of the body and the jaws includes at least one aperture. At least one connector extends through the aligned slot or slots and aperture or apertures. At least one spring is oriented on the connector or connectors and between the body and the jaws.
Further illustratively according to this aspect of the invention, the apparatus includes a bias mechanism for yieldably biasing the jaws toward their extended orientations.
Illustratively according to this aspect of the invention, the body includes at least one bore. The bias mechanism includes a plunger and a spring yieldably urging the plunger from the at least one bore and the plunger is coupled to the clamp.
According to another aspect of the invention, a method is provided for attaching an imbalance correction weight to a rotary element to reduce an imbalance in the rotary element. The imbalance correction weight including one or more individual weights provided on a first side of a length of tape. The tape includes a second side for attachment to the rotary element. The method includes holding the imbalance correction weight by a clamp, pressing the clamp against the rotary element, and releasing the imbalance correction weight from the clamp in contact with the rotary element.
Illustratively according to this aspect of the invention, holding the imbalance correction weight by a clamp includes providing a channel in the clamp and positioning at least a portion of the imbalance correction weight in the channel.
Further illustratively according to this aspect of the invention, pressing the clamp against the rotary element and releasing the imbalance correction weight from the clamp together include moving the at least a portion of the imbalance correction weight outside the channel.
Additionally illustratively according to this aspect of the invention, pressing the clamp against the rotary element and releasing the imbalance correction weight from the clamp together include retracting a pair of jaws of the clamp with respect to a body provided for pressing the imbalance correction weight against the rotary element.
Illustratively according to this aspect of the invention, retracting a pair of jaws of the clamp with respect to a body provided for pressing the imbalance correction weight against the rotary element includes moving the jaws away from one another.
Further illustratively according to this aspect of the invention, releasing the imbalance correction weight from the clamp includes moving the imbalance correction weight out of grooves formed in the jaws. The grooves face each other. The imbalance correction weight moves to a position outside the grooves in which the jaws cooperate to hold the imbalance correction weight.
Additionally illustratively according to this aspect of the invention, pressing the clamp against the rotary element and releasing the imbalance correction weight from the clamp together include rolling the clamp against the rotary element.
Illustratively according to this aspect of the invention, rolling the clamp against the rotary element includes rolling a convex surface of the clamp against a concave surface of the rotary element which has a radius of curvature greater than a radius of curvature of the convex surface of the clamp.
Further illustratively according to this aspect of the invention, holding the imbalance correction weight by a clamp includes holding the imbalance correction weight by a pair of jaws of the clamp. Each jaw includes a convex surface. Rolling a convex surface of the clamp against a concave surface of the rotary element which has a radius of curvature greater than a radius of curvature of the convex surface of the clamp includes rolling the convex surfaces of the jaws against the concave surface of the rotary element.